Hi J so I think your problem here stems from your profiles having a different number of segments in them. The top curve is made up of 12 segments while the middle and bottom ones have 8 segments each. You can still loft with those but when the number of segments don't match it's going to do an automated process of cutting them up into smaller pieces to connect them and that automated process probably won't be as good as if you used your own judgement to match things to each other.

So one thing that could help is to divide your 8-segmented curves up so they also have 12 segments in them and then with all curves having the same number of segments it will be able to make a 1-to-1 connection between the segments.

Another thing that can also control matching better is if you do it in some smaller pieces, like this: (also see attached .3dm file):







- Michael